UKM Sync Observer

components/ukm/observers/sync_disable_observer.cc

Index: components/ukm/observers/sync_disable_observer.cc
diff --git a/components/ukm/observers/sync_disable_observer.cc b/components/ukm/observers/sync_disable_observer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..697a1609422ac1c9fd53a40d846faaaa9f1d9ff5
--- /dev/null
+++ b/components/ukm/observers/sync_disable_observer.cc
@@ -0,0 +1,71 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/ukm/observers/sync_disable_observer.h"
+
+namespace ukm {
+
+SyncDisableObserver::SyncDisableObserver()
+    : sync_observer_(this), all_profiles_enabled_(false) {}
+
+SyncDisableObserver::~SyncDisableObserver() {}
+
+// static
+bool SyncDisableObserver::IsHistorySyncEnabled(
+    syncer::SyncService* sync_service) {
+  return sync_service &&
+         sync_service->GetPreferredDataTypes().Has(

[rkaplow, 2017/02/01 16:40:55]

can you comment on this

[Steven Holte, 2017/02/03 00:04:34]

Done.

+             syncer::HISTORY_DELETE_DIRECTIVES);
+}
+
+void SyncDisableObserver::ObserveServiceForSyncDisables(
+    syncer::SyncService* sync_service) {
+  was_enabled_map_[sync_service] = IsHistorySyncEnabled(sync_service);
+  sync_observer_.Add(sync_service);
+  UpdateAllProfileEnabled(false);
+}
+
+void SyncDisableObserver::UpdateAllProfileEnabled(bool must_purge) {
+  // If there are no services, default to being disabled.
+  if (was_enabled_map_.empty()) {
+    all_profiles_enabled_ = false;
+    OnSyncPrefsChanged(must_purge);
+    return;
+  }
+
+  bool all_enabled = true;
+  for (auto const& kv : was_enabled_map_) {

[Alexei Svitkine (slow), 2017/02/01 19:31:07]

Nit: const auto&

[Steven Holte, 2017/02/03 00:04:34]

Done.

+    if (!kv.second) {
+      all_enabled = false;
+      break;
+    }
+  }
+  if (must_purge || (all_enabled != all_profiles_enabled_)) {
+    all_profiles_enabled_ = all_enabled;
+    OnSyncPrefsChanged(must_purge);
+  }
+}
+
+void SyncDisableObserver::OnSyncConfigurationCompleted(
+    syncer::SyncService* sync) {
+  DCHECK(was_enabled_map_.find(sync) != was_enabled_map_.end());

[Alexei Svitkine (slow), 2017/02/01 19:31:07]

Nit: !ContainsKey()

[Steven Holte, 2017/02/03 00:04:34]

Done.

+
+  bool is_enabled = IsHistorySyncEnabled(sync);
+  bool must_purge = was_enabled_map_[sync] && !is_enabled;
+  was_enabled_map_[sync] = is_enabled;
+  UpdateAllProfileEnabled(must_purge);
+}
+
+void SyncDisableObserver::OnSyncShutdown(syncer::SyncService* sync) {
+  DCHECK(was_enabled_map_.find(sync) != was_enabled_map_.end());
+  sync_observer_.Remove(sync);
+  was_enabled_map_.erase(sync);
+  UpdateAllProfileEnabled(false);
+}
+
+bool SyncDisableObserver::IsHistorySyncEnabledOnAllProfiles() {
+  return all_profiles_enabled_;
+}
+
+}  // namespace ukm